The New Castle Subdivision is a railroad line owned and operated by CSX Transportation in the U.S. states of Pennsylvania and Ohio.

The Pittsburgh, Cleveland and Toledo Railroad opened tracks from New Castle to Youngstown and a line continuing west to Valley Junction (near Akron, Ohio) in 1884.

On August 1, 1887, much of PC&T's railway was leased by the Pittsburgh and Western Railway Company for passenger service directly between Chicago, Illinois to Philadelphia, Pennsylvania.

[8] As the P&LE improved their single-track line, B&O's route followed a similar path between Pittsburgh and Youngstown.

Chessie System later merged with Seaboard Coast Line Industries to form CSX in 1980.